The Support spring is housed between the valve piston and the black adjustment cap. Its role is to exercise a constant reminder force on the guillotine to keep it in the low position. It is the resistance of this spring that defines when (which engine speed) the pressure of the gases will be able to lift the valve to release the power.

The Adjustment screw, located at the top of the valve hood, is the direct interface between the driver and the engine. By screwing it or by unscrewing it, the preload of the internal spring is modified, which defines which precise regime will open to release all the power of the Rotax.

The cylinder head cap Rotax 10 mm (engraved 1.8 torque) is a spare part of origin manufacturer (Original Rotax Racing). It is designed to tightly seal one of the threaded cylinder head orifices (cylinder cover) on all the engines of the range Rotax 125 Max (Micro, Mini, Junior, Max Senior, Max Master and DD2).

Machined according to strict micrometric tolerances, this brass plug or high strength alloy has a thread of 10 mm. Its flat head includes plant engraving "1.8 Torque", indicating the pilots and mechanics the regulatory torque recommended by the plant (1.8 N · m) not to damage the aluminum thread of the cylinder head. This plug ensures absolute sealing of the liquid cooling circuit, avoiding any pressure drop or heat transfer leak at high speed.

Rotax Valve Hood Fixing Spring - Land 17 This high-strength steel spring ensures firm and secure holding of the hood of your exhaust valve. Original room RotaxIt guarantees the pressure necessary for the valve system to operate constantly, thus avoiding the untimely openings or the compression losses.

TheM8 base nut is the attachment element that engages the cylinder at the bottom motor (housing). On an engine Rotax Max, there are four, positioned at the corners of the base. Their role is to maintain a constant pressure on the base gasket to ensure the sealing and absorb explosion and vibration constraints.

The 64x2mm O-ring is the internal seal located between the dome of the cylinder head and the cylinder. Its precise dimensions (64 mm inner diameter and 2 mm thick) are designed to fit perfectly into the cylinder groove, preventing the cooling liquid from seeping into the combustion chamber.

The Cylinder head Rotax MAX / DD2 is the red upper piece that seals the high engine. She is 100% compatible with the entire 125cc range from Rotax, including direct socket motors (MAX) and two-speed engines (Dd2). It ensures the circulation of the coolant around the combustion dome for perfect thermal stability.

The M8 Stop Washer (N ° 21) is a security technical washer placed between the nut and the cylinder base. Its role is to prevent any inconvenient loosening of the high engine mount nuts. On the DD2 motor, where the vibrations and transmission stresses are important, it is essential to ensure the integrity of the motor block.

The Screw th m8x30mm (n ° 22) is a high-quality hexagonal head screw used to bridge the cylinder on the motor housing of the Rotax Dd2. With its length of 30 mm and its thread M8It ensures a solid grip in the low engine nets. She works in pairs with the stop washer (n ° 21) to ensure that the cylinder remains perfectly motionless despite repeated explosions.

The Cylinder head seal 105 x 2.5 mm is the large peripheral O-ring that ensures the sealing of the cooling circuit between the cylinder and the red cylinder head. Designed according to the strict standards of RotaxIt supports high pressures and extreme thermal variations, ensuring that the cooling liquid remains perfectly confined in its circuit.

The Red cylinder head (ref. Rotax 211225) is the upper structural element that closes the high engine cooling circuit. Real visual signature of engines RotaxThis injected aluminum alloy part is designed to withstand the most intense thermal and vibratory stresses, ensuring the overall waterproofing of the water chamber.

Cylinder head cover Rotax Max not painted

TheFull valve box Rotax EVO20is an original manufacturer part designed for motors Rotax from 2020. It ensures optimum intake management of the air/fuel mixture and ensures proper operation and engine performance.

This version corresponds to engines equipped with the EVO 2020 configuration.

The valve box cover, commonly called intake blowjob, is a centerpiece of your engine intake system Rotax. This model, with a connecting diameter of 42.5 mm, is designed to perfectly accommodate the dell'orto VHSB 34 carburetor.